Patent EP0091653A2 successfully refreshed from Google Patents.
EP0091653A2
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Rotational plastic compression molding apparatus
Assignee: Nippon Closures Co Ltd
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Filing: 1983-04-06
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Granted: —
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Expires: 2003-04-06
Abstract
Abstract O A rotational plastic compression molding apparatus including a plurality of circumferentially spaced female molds (38) and a plurality of circumferentially spaced male molds (34) cooperating respectively with the plurality of the female molds (38). The female molds and the male molds are rotated in synchronism and thus moved round successively through a material loading zone (A), a compression molding zone (B) and an article discharge zone (C). In the material loading zone (A) and the article discharge zone (C), each said female mold (38) and each corresponding male mold (34) are maintained in a spaced-apart inoperative relation, and in the compression molding zone (B), they are maintained in an approaching operative relation to define a mold space therebetween. In the material loading zone (A), a heat-melted plastic material is loaded in the female molds (38), and in the article discharge zone (C), the compression-molded plastic article is discharged from between each said female mold (38) and each corresponding male mold (34).
Inventors
- 👤 Kashiwa Murayama
- 👤 Osamu Ishii
- 👤 Yoshiaki Mochino
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 22:08
CPC Classifications
B; B29; B29C; B29C43/00; B29C43/32; B29C43/34; B29C43/02; B29C43/04; B29C43/06; B29C43/08; B29C43/36; B29C43/42; B29C43/50; B29C2043/3272; B29C2043/3283; B29C2043/3288; B29C2043/3676; B29C2043/3689; B29C33/00; B29C33/34; B29C33/36; B29L; B29L2001/00; B29L2031/00; B29L2031/56; B29L2031/565; Y; Y10; Y10S; Y10S425/00; Y10S425/20; Y10S425/201; Y10S425/809
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
177 words
A rotational plastic compression molding apparatus comprising a plurality of circumferentially spaced female molds (38), a plurality of circumferentially spaced male molds (34) cooperating respectively with the plurality of the female molds (38), rotationally driving means (42) for rotating the female molds and the male molds in synchronism, thereby moving them round successively through a material loading zone (A), a compression molding zone (B) and an article discharge zone (C), mold relation control means (18, 158; 20, 168) for maintaining each said female mold (38) and each corresponding male mold (34) in a spaced-apart inoperative relation in the material loading zone (A) and the article discharge zone (C), and in an approaching operative relation to define a mold space therebetween in the compression molding zone (B), material loading means (170) for loading a heat-melted plastic material into the female molds (38) in the material loading zone (A), and article discharge means (182) for discharging the compression-molded plastic article from between each said female mold (38) and each corresponding male mold (34) in the article discharge zone (C).
Claim 2
Dependent Claim
177 words
A rotational plastic compression molding apparatus comprising a plurality of circumferentially spaced female molds (38), a plurality of circumferentially spaced male molds (34) cooperating respectively with the plurality of the female molds (38), rotationally driving means (42) for rotating the female molds and the male molds in synchronism, thereby moving them round successively through a material loading zone (A), a compression molding zone (B) and an article discharge zone (C), mold relation control means (18, 158; 20, 168) for maintaining each said female mold (38) and each corresponding male mold (34) in a spaced-apart inoperative relation in the material loading zone (A) and the article discharge zone (C), and in an approaching operative relation to define a mold space therebetween in the compression molding zone (B), material loading means (170) for loading a heat-melted plastic material into the female molds (38) in the material loading zone (A), and article discharge means (182) for discharging the compression-molded plastic article from between each said female mold (38) and each corresponding male mold (34) in the article discharge zone (C).
Claim 3
Dependent Claim
21 words
The apparatus of claim 1 wherein the rotationally driving means (42) rotates the female molds (38) and male molds (34) continuously.
Claim 4
Dependent Claim
48 words
The apparatus of claim 2 which further comprises heating means (184) for heating at least the female molds (38) at least between the article discharge zone (C) and the material loading zone (A), and cooling means for circulating a cooling medium at least to the female molds (38).
Claim 5
Dependent Claim
18 words
The apparatus of claim 3 wherein the heating means (184) is constructed of a high frequency induction heater.
Claim 6
Dependent Claim
19 words
The apparatus of claim 3 wherein the cooling means circulates the cooling medium also to the male molds (34).
Claim 7
Dependent Claim
98 words
The apparatus of claim 1 wherein the plastic article to be compression-molded is a container closure having a top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of the top panel wall; and wherein the outside surface of the top panel wall of the closure and at least a greater portion of the outside surface of the skirt wall are defined by each said female mold, and the inside surface of the top panel wall of the closure and the inside surface of the skirt wall are defined by each said male mold.
Claim 8
Dependent Claim
115 words
The apparatus of claim 6 wherein each said male mold (34) includes a sliding piece (148) disposed for free movement from its normal position in a direction away from the corresponding female mold, the forward end surface of the sliding piece defining at least a part of the inside surface of the top panel wall of the container closure, and spring means (152) for elastically biasing the sliding piece to said normal position, and when the pressure acting on the plastic material in the mold space becomes excessive, the sliding piece is moved from the normal position in the direction away from the corresponding female mold against the elastic biasing action of the spring member.
Claim 9
Dependent Claim
118 words
The apparatus of claim 6 wherein each said male mold (34) includes a sliding piece (448) disposed for free movement from its normal position in a direction away from the corresponding female mold, the forward end surface of the sliding piece defining a part of the inside surface of the top panel wall of the container closure, and means (424, 425, 427, 454) for forcibly holding the sliding piece (448) at said normal position releasably, and when the pressure acting on the plastic material in the mold space becomes excessive, the forcible holding action of said means is released to move the sliding piece (448) from said normal position in the direction away from the corresponding female mold.
Claim 10
Dependent Claim
51 words
The apparatus of claim 8 wherein a stress measuring device (401) for measuring the stress acting on each said male mold is provided, and when the measured value obtained by the stress measuring device exceeds a predetermined value, the forcibly holding action of said means (424, 425, 427, 454) is released.
Claim 11
Dependent Claim
23 words
The apparatus of claim 8 wherein said forcibly holding means forcibly holds the sliding piece (448) at the normal position by fluid pressure.
Claim 12
Dependent Claim
28 words
The apparatus of claim 7 wherein the forward end surface of the sliding piece (448) defines the central part of the inside surface of the top panel wall.
Claim 13
Dependent Claim
114 words
The apparatus of claim 6 wherein each of said female mold (38) includes a sliding piece disposed for free movement from its normal position in a direction away from the corresponding male mold, the forward end surface of the sliding piece defining at least a part of the outside surface of the top panel wall of the container closure, and spring means for elastically biasing the sliding piece to said normal position, and when the pressure acting on the plastic material in the mold space becomes excessive, the sliding piece is moved from said normal position in the direction away from the corresponding male mold against the elastic biasing action of the spring means.
Claim 14
Dependent Claim
114 words
The apparatus of claim 6 wherein each said female mold (38) includes a sliding piece disposed for free movement from its normal position in a direction away from the corresponding male mold, the forward end surface of the sliding piece defining a part of the outside surface of the top panel wall of the container closure, and means for forcibly holding the sliding piece at said normal position releasably, and when the pressure acting on the plastic material in the mold space becomes excessive, the forcibly holding action of said forcibly holding means is released, and the sliding piece is moved from said normal position in the direction away from the corresponding male mold.
Claim 15
Dependent Claim
48 words
The apparatus of claim 13 wherein a stress measuring device for measuring the stress acting on each said female mold is provided, and when the measured value obtained by the stress measuring device exceeds a predetermined value, the forcibly holding action of said forcibly holding means is released.
Claim 16
Dependent Claim
22 words
The apparatus of claim 13 wherein the forcibly holding means forcibly holds the sliding piece at said normal position by fluid pressure.
Claim 17
Dependent Claim
27 words
The apparatus of claim 12 wherein the forward end surface of the sliding piece defines the central part of the outside surface of the top panel wall.
References Cited (Backward Citations)
No citation records indexed.
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